Declaring Directional Comma

Question

Does this offer declare two pointers or a pointer and an object? Is this true for any type of variable?

int* x, y;

Harry Harry 106k 9 54 132 · Accepted Answer · 2017-02-08T17:40:42

int* x, y; - pointer x and integer variable y .

* refers to a variable , not a type .

Declare a type using typedef (or in C ++ using using ) - then another thing:

 typedef int * pint; pint x, y;

Here both x and y are pointers to int .

Harry

106k 9 54 132

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Never do typedef int * pint; in C. - 0andriy
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@ 0andriy <irony_mode> Win API does not agree with you! </ Irony_mode> - Monah Tuk
@ 0andriy Share how it should be done then. - Harry
@ 0andriy, why? I remember about define, but what’s wrong here? - Qwertiy ♦
@Harry, use explicitly. It makes sense for opaque pointers , for POD this makes the code error prone (remember for example that implicit casting type * in void * works), the const qualifier is bad with that. You can read stackoverflow.com/questions/3781932 with comments and answers, then follow the link there. - 0andriy

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Qwertiy ♦ Qwertiy 76.3k 17 74 201 · Answer 2 · 2017-02-08T17:40:43

Pointer and non pointer.
Therefore, it is customary to write an asterisk in front of the variable name, not in front of the type.

 #include <stdio.h> int main() { short *a, b; printf("%zu %zu\n", sizeof a, sizeof b); return 0; }

It is generally accepted to write every identifier on a new line with a type.
@alexolut, firstly, does not interfere with one another - it is quite possible to write one ad on a line and at the same time put an asterisk in front of the name.
And secondly, I would argue that it is really customary to write one per line.

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